<PAGE>
                                                                          

                                                      Exhibit (3)-3
                                                      Unicom Corporation
                                                      Form 10-K File No. 1-11375



                              Unicom Corporation

                                    By-Laws


                          Effective January 28, 1994

                              As Amended Through

                               January 29, 1997
<PAGE>
 
                                  CONTENTS

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                                                                         Page
                                                                        Number
                                                                        ------
<S>                                                                       <C>

ARTICLE I.       Stock..................................................   1

ARTICLE II.      Meetings of Shareholders...............................   3

ARTICLE III.     Board of Directors.....................................   5

ARTICLE IV.      Committees of the Board of Directors...................   7

ARTICLE V.       Officers...............................................  11

ARTICLE VI.      Indemnification........................................  15

ARTICLE VII.     Miscellaneous..........................................  17

ARTICLE VIII.    Alteration, Amendment or Repeal of By-Laws.............  17
</TABLE>
<PAGE>
 
                              Unicom Corporation

                                    By-Laws

                                     -----

                                  ARTICLE I.

                                    STOCK.


          SECTION 1.  Each holder of fully paid stock shall be entitled to a
certificate or certificates of stock stating the number and class of shares,
and the designation of the series, if any, which such certificate represents.
All certificates of stock shall at the time of their issuance be signed either
manually or by facsimile signature by the Chairman, the President or a Vice
President and by the Secretary or an Assistant Secretary.  All certificates of
stock shall be sealed with the seal of the Company or a facsimile of such
seal, shall be countersigned either manually or by facsimile signature by a
Transfer Agent and shall be authenticated by manual signature and registered
by a Registrar.  The Board of Directors shall appoint one or more Transfer
Agents, none of whom shall be officers of the Company authorized to sign
certificates of stock, and one or more Registrars, each of which Registrars
shall be a bank or trust company.  Certificates of stock shall not be valid
until countersigned by a Transfer Agent and authenticated and registered by a
Registrar in the manner provided by the Board of Directors.

          SECTION 2. Shares of stock shall be transferable only on the books of
the Company and, except as hereinafter provided or as otherwise required by law,
shall be transferred only upon proper endorsement and surrender of the
certificates issued therefor. If an outstanding certificate of stock shall be
lost, destroyed or stolen, the holder thereof may have a new certificate upon
producing evidence satisfactory to the Board of Directors of such loss,
destruction or theft, and upon furnishing to the Company, the Transfer Agents
and the Registrars a bond of indemnity deemed sufficient by the Board of
Directors against claims under the outstanding certificate.

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<PAGE>
 
          SECTION 3.  The certificates for each class or series of stock shall
be numbered and issued in consecutive order and a record shall be kept of the
name and address of the person to whom each certificate is issued, the number
of shares represented by the certificate and the number and date of the
certificate.  All certificates exchanged or returned to the Company or the
Transfer Agent for transfer shall be canceled and filed.


          SECTION 4. For the purpose of determining shareholders entitled to
notice of or to vote at any meeting of shareholders, or shareholders entitled to
receive payment of any dividend, or in order to make a determination of
shareholders for any other proper purpose, the Board of Directors may fix in
advance a date as the record date for any such determination of shareholders,
such date in any case to be not more than sixty days and, for a meeting of
shareholders, not less than ten days, or in the case of a merger, consolidation,
share exchange, dissolution or sale, lease or exchange of assets, not less than
twenty days, immediately preceding such meeting.

          SECTION 5. If any subscription for stock in the Company or any
installment of such subscription shall be unpaid when due, as the Board of
Directors shall have determined the time for payment, and shall continue unpaid
for twenty days after demand for the amount due, made either in person or by
written notice duly mailed to the last address, as it appears on the records of
the Company, of the subscriber or other person by whom the subscription or
installment shall be payable, the stock or subscription upon which payment shall
be so due shall, upon the expiration of said twenty days, become and be
forfeited to the Company without further action, demand or notice, and such
stock or subscription may be sold at public sale, subject to payment of the
amount due and unpaid, plus all costs and expenses incurred by the Company in
that connection, at a time and place to be stated in a written notice to be
mailed to the recorded address of the delinquent subscriber or other person in
default on the subscription at least ten days prior to the time fixed for such
sale; provided, that the excess of proceeds of such sale realized over the
amount due and unpaid on said stock or subscription shall be paid to the
delinquent subscriber of other person in default on the subscription, or to his
or her legal representative; and, provided further, that no forfeiture of stock,
or of any amounts paid upon
                           
                                      -2-
<PAGE>
 
a subscription therefor, shall be declared as against the estate of any decedent
before distribution shall have been made of the estate.

          The foregoing provisions for the forfeiture and sale of stock or
subscriptions shall not exclude any other remedy which may lawfully be
enforceable at any time, by forfeiture of stock or of amounts theretofore paid
or otherwise, against any person for nonpayment of a subscription or of any
installment thereof.

          SECTION 6.  Transfers of shares shall be made only on the books of the
Company by the registered holder thereof or by his or her legal representative,
who shall furnish proper evidence of authority to transfer, or by his or her
attorney or successor thereunto authorized by power of attorney or by documents
duly executed and filed with the Secretary or Transfer Agent of the Company, and
upon surrender for cancellation of the certificate for such shares. The person
in whose name shares stand on the books of the Company shall be deemed the owner
thereof for all purposes as regards the Company.

          SECTION 7.  The Company shall be entitled to treat the holder of
record of any share or shares of stock as the holder in fact thereof and
accordingly, shall not be bound to recognize any equitable or other claim to or
interest in such share or shares on the part of any other person, whether or not
it shall have express or other notice thereof, except as otherwise provided by
the laws of the State of Illinois.


                                  ARTICLE II.

                           MEETINGS OF SHAREHOLDERS.

          SECTION 1.  The regular annual meeting of the shareholders of the
Company for the election of Directors and for the transaction of such other
business as may come before the meeting shall be held on such day in April or
May of each year as the Board of Directors may by resolution determine. Each
such regular annual meeting and each special meeting of the shareholders shall
be held at such place as may be fixed by the Board of Directors and at such hour
as the Board of Directors shall order.

                                      -3-
<PAGE>
 
          SECTION 2.  Special meetings of the shareholders may be called by the
Chairman, by the Board of Directors, by a majority of the Directors individually
or by the holders of not less than one-fifth of the total outstanding shares of
capital stock of the Company.

          SECTION 3.  Written notice stating the place, day and hour of the
meeting of the shareholders and, in the case of a special meeting, the purpose
or purposes for which the meeting is called shall be delivered not less than ten
nor more than sixty days before the date of the meeting, or in the case of a
merger, consolidation, share exchange, dissolution or sale, lease or exchange of
assets not less than twenty nor more than sixty days before the date of the
meeting, either personally or by mail, by or at the direction of the Chairman,
the Secretary or the persons calling the meeting, to each shareholder of record
entitled to vote at such meeting. If mailed, such notice shall be deemed to be
delivered when deposited in the United States mail addressed to the shareholder
at the shareholder's address as it appears upon the records of the Company, with
postage thereon prepaid.

          SECTION 4.  At all meetings of the shareholders, a majority of the
outstanding shares of stock, entitled to vote on a matter, represented in person
or by proxy, shall constitute a quorum for consideration of such matter, but the
shareholders represented at any meeting, though less than a quorum, may adjourn
the meeting to some other day or sine die. If a quorum is present, the
affirmative vote of the majority of the shares of stock represented at the
meeting and entitled to vote on a matter shall be the act of the shareholders,
unless the vote of a greater number or voting by classes is required by law or
the articles of incorporation.

          SECTION 5.  At every meeting of the shareholders, each outstanding
share of stock shall be entitled to one vote on each matter submitted for a
vote. In all elections for Directors, every shareholder shall have the right to
vote the number of shares owned by such shareholder for as many persons as there
are Directors to be elected, or to cumulate such votes and give one candidate as
many votes as shall equal the number of Directors to be elected multiplied by
the number of such shares or to distribute such cumulative votes in any
proportion among any number of candidates. A shareholder may vote either in
person or by proxy.
                                      
                                      -4-
<PAGE>
 
A shareholder may appoint a proxy to vote or otherwise act for him or her by
signing an appointment form and delivering it to the person so appointed.

          SECTION 6.  Any meeting at which a quorum of shareholders is present,
in person or by proxy, may adjourn from time to time without notice, other than
announcement at such meeting, until its business is completed. At the adjourned
meeting, the Company may transact any business which might have been transacted
at the original meeting. If the adjournment is for more than thirty days, a
notice of the adjourned meeting shall be given to each shareholder of record
entitled to vote at the meeting.

          SECTION 7.  The Secretary of the Company shall make or cause to be
made, within twenty days after the record date for a meeting of shareholders of
the Company or ten days before such meeting, whichever is earlier, a complete
list of the shareholders entitled to vote at such meeting, arranged in
alphabetical order, with the address of and the number of shares held by each,
which list, for at least ten days prior to such meeting, shall be kept on file
at the registered office of the Company and shall be subject to inspection by
any shareholder, and to copying at such shareholder's expense, at any time
during usual business hours. Such list shall also be produced and kept open at
the time and place of the meeting and shall be subject to the inspection of any
shareholder during the whole time of the meeting.

          SECTION 8.  The Chairman and the Secretary of the Company shall, when
present, act as chairman and secretary, respectively, of each meeting of the
shareholders.

          SECTION 9.  At any meeting of shareholders, the chairman of the
meeting may, or upon the request of any shareholder shall, appoint one or more
persons as inspectors for such meeting, unless an inspector or inspectors shall
have been previously appointed for such meeting by the Chairman. Such inspectors
shall ascertain and report the number of shares of stock represented at the
meeting, based upon their determination of the validity and effect of proxies,
count all votes and report the results and do such other acts as are proper to
conduct the election and voting with impartiality and fairness to all the
shareholders.

                                      -5-
<PAGE>
 
          SECTION 10.  Voting on any question or in any election may be viva
voce unless the presiding officer shall order or any shareholder shall demand
that voting be by ballot.


                                 ARTICLE III.

                              BOARD OF DIRECTORS.

          SECTION 1.  The business and affairs of the Company shall be managed
by or under the direction of the Board of Directors. The number of Directors of
the Company shall be not less than ten nor more than fifteen. The Directors
shall be elected at each annual meeting of the shareholders, but if for any
reason the election shall not be held at an annual meeting, it may be
subsequently held at any special meeting of the shareholders called for that
purpose after proper notice. The Directors so elected shall hold office until
the next annual meeting and until their respective successors, willing to serve,
shall have been elected and qualified. Directors need not be residents of the
State of Illinois or shareholders of the Company. No person shall be eligible
for nomination or renomination as a Director by the management of the Company
who, prior to the date of election, shall have attained age seventy-two. No
person who is an employe or a former employe of the Company or of a subsidiary
of the Company shall be eligible for nomination or renomination as a Director by
the management of the Company for a term commencing after such person ceases to
be such an employe; provided, however, that any Director of the Company who was
a Director of Commonwealth Edison Company, an Illinois corporation, in office on
June 15, 1989 who is or has been such an employe may be renominated as a
Director unless such person shall have attained age sixty-five on or before the
date of election of Directors.

          SECTION 2.  Any vacancy occurring in the Board of Directors, including
a vacancy created by an increase in the number of directors, may be filled by
election at an annual meeting or at a special meeting of shareholders called for
that purpose; provided, however, that any vacancy in the Board of Directors
arising between meetings of shareholders by reason of an increase in the number
of directors or otherwise may be filled by the vote of a majority of the
directors then in office, although less than

                                      -6-
<PAGE>
 
a quorum. Any directors so elected shall serve until the next annual meeting of
shareholders.

          SECTION 3.  A meeting of the Board of Directors shall be held
immediately, or as soon as practicable, after the annual election of Directors
in each year, provided a quorum for such meeting can be obtained. Notice of
every meeting of the Board, stating the time and place at which such meeting
will be held, shall be given to each Director personally, by telephone or by
other means of communication at least one day, or by depositing the same in the
mails properly addressed at least two days before the day of such meeting. A
meeting of the Board of Directors may be called at any time by the Chairman or
by any two Directors and shall be held at such place as shall be specified in
the notice for such meeting.

          SECTION 4.  A majority of the number of Directors then in office, but
not less than six, shall constitute a quorum for the transaction of business at
any meeting of the Board, but a lesser number may adjourn the meeting from time
to time until a quorum is obtained, or may adjourn sine die. The act of the
majority of the Directors present at a meeting at which a quorum is present
shall be the act of the Board of Directors.

          SECTION 5.  Each member of the Board not receiving a salary from the
Company or a subsidiary of the Company shall be paid such fees as the Board of
Directors may from time to time, by resolution adopted by the affirmative vote
of a majority of the Directors then in office, and irrespective of any personal
interest of any of its members, determine. The Directors shall be paid their
reasonable expenses, if any, of attendance at each meeting of the Board of
Directors. Members of any committee of the Board of Directors may be allowed
like fees and expenses for service on or attendance at meetings of such
committee. No such payment shall preclude any Director from serving the Company
in any other capacity and receiving compensation therefor.

          SECTION 6.  A Director of the Company who is present at a meeting of
the Board of Directors at which action is taken on any corporate matter shall be
conclusively presumed to have assented to the action taken unless his or her
dissent shall be entered in the minutes of the meeting or unless he shall file
his or her written dissent to such action with the person acting as Secre-

                                      -7-
<PAGE>
 
tary of the meeting before the adjournment thereof or shall forward such dissent
by registered mail to the Secretary of the Company immediately after the
adjournment of the meeting. Such right to dissent shall not apply to a director
who voted in favor of such action.

          SECTION 7.  At the first meeting of the Board of Directors following
the annual meeting of shareholders each year, the Board shall elect a Lead
Director. The Lead Director shall be elected from among the Outside Directors of
the Company. For purposes hereof, "Outside Directors" shall be those who are not
and never have been employees of the Company or any of its direct or indirect
subsidiaries. The duties of the Lead Director shall be to convene and chair
meetings of the Outside Directors and to assume other responsibilities which the
Outside Directors might designate from time to time. The Lead Director will
consult with other Outside Directors as to appropriate items for discussion at
each such meeting.

                                 ARTICLE IV.

                     COMMITTEES OF THE BOARD OF DIRECTORS

          SECTION 1.  There shall be an Executive Committee of the Board
consisting of six members. The Board of Directors shall, at its first meeting
after the annual meeting of the shareholders in each year, elect a chairman and
the four other members of the Executive Committee. The remaining Directors shall
constitute alternates to serve temporarily, and as far as practicable in
rotation (in such order as shall be established by the Board), in the place of
any member who may be unable to serve. The Chairman or the Directors calling a
meeting of the Executive Committee shall call upon alternates, in rotation, to
serve as herein provided. When any alternate serves, the minutes of the meeting
shall record the name of the member in whose place such alternate serves. The
Directors elected as members of the Executive Committee shall serve as such for
one year and until their respective successors, willing to serve, shall have
been elected. The Executive Committee shall, when the Board is not in session,
have and may exercise all of the authority of the Board of Directors, subject to
the limitations set forth in Section 10 of this Article IV. Vacancies in the
membership of the Executive Committee shall be filled by the Board of Directors.
The Execu-

                                      -8-
<PAGE>
 
      tive Committee shall keep minutes of the proceedings at
      its meetings.

          SECTION 2. There shall be an Audit Committee of the Board consisting
      of not less than three nor more than five members who are not employes of
      the Company. The Directors elected as members of the Audit Committee shall
      serve as such for three years and until their respective successors,
      willing to serve, shall have been elected, provided that, to the extent
      practicable, the members of the Audit Committee shall be elected for
      staggered terms. The Board of Directors shall, at its first meeting after
      the annual meeting of shareholders in each year, elect the successors of
      the members whose terms shall then expire. The Board of Directors shall
      designate from time to time the member who is to serve as chairman of the
      Audit Committee. The Audit Committee shall meet with the Company's
      independent auditors at least once each year to review the Company's
      financial statements and the scope and results of such auditors'
      examinations, monitor the internal accounting controls and practices of
      the Company, review the annual report to shareholders and made
      recommendations as to its approval to the Board and recommend, subject to
      shareholder approval, the appointment of independent auditors, and shall
      report its findings at least once each year to the Board. The Audit
      Committee shall have such powers as it shall deem necessary for the
      performance of its duties. Vacancies in the membership of the Audit
      Committee shall be filled by the Board of Directors. The Audit Committee
      shall keep minutes of the proceedings at its meetings.

          SECTION 3. There shall be a Corporate Governance and Compensation
      Committee of the Board consisting of those Directors who are not employees
      or former employees of the Company. The Board of Directors shall, at its
      first meeting after the annual meeting of shareholders in each year, elect
      a chairman of the Corporate Governance and Compensation Committee. The
      Directors serving as members of the Committee shall serve for one year and
      until their respective successors, willing to serve, shall have been
      elected. The Corporate Governance and Compensation Committee shall (i)
      oversee corporate governance policies, practices and procedures of the
      Company and make such recommendations as it may deem appropriate to the
      Board; and (ii) oversee general compensation policy of the Company, and
      establish and administer compensation programs applicable to the principal

                                      -9-
<PAGE>
 
     officers of the Company, including but not necessarily limited to the
     establishment of base salaries and the administration of awards under the
     Unicom Corporation Deferred Compensation Unit Plan and the Unicom
     Corporation Long-Term Incentive Plan. The Committee shall have such power
     as it deems necessary for the performance of its duties. Vacancies in the
     membership of the Committee shall be filled by the Board of Directors. The
     Committee shall keep minutes of the proceedings at its meetings.

          SECTION 4. There shall be a Finance Committee of the Board consisting
     of not less than three nor more than five members. The Board of Directors
     shall, at its first meeting after the annual meeting of shareholders in
     each year, elect a chairman and the other members of the Finance Committee.
     The Directors elected as members of the Finance Committee shall serve as
     such for one year and until their respective successors, willing to serve,
     shall have been elected. The Finance Committee shall review the scope and
     results of the Company's financing program and review the Company's
     financial statements, construction budgets and cash budgets as they relate
     to the Company's financing program, and shall report its findings at least
     once each year to the Board. The Finance Committee shall have such power as
     it shall deem necessary for the performance of its duties. Vacancies in the
     membership of the Finance Committee shall be filled by the Board of
     Directors. The Finance Committee shall keep minutes of the proceedings at
     its meetings.

          SECTION 5. There shall be a Nominating Committee of the Board
     consisting of not less than three nor more than five members, a majority of
     whom are not employes of the Company. The Board of Directors shall, at its
     first meeting after the annual meeting of shareholders in each year, elect
     a chairman and the other members of the Nominating Committee. The Directors
     elected as members of the Nominating Committee shall serve as such for one
     year and until their respective successors, willing to serve, shall have
     been elected. The Nominating Committee shall review the requirements for
     serving as Director, review potential candidates for Director, propose
     nominees for Director to the Board and recommend to the Board the successor
     to the Chairman when a vacancy occurs in that position. The Nominating
     Committee shall have such power as it shall deem necessary for the
     performance of its duties. Vacancies in the membership of the Nominating
     Committee shall be filled by the Board of Directors. The

                                     -10-
<PAGE>
 
     Nominating Committee shall keep minutes of the proceedings at its meetings.

          SECTION 6. The Board of Directors may from time to time create other
     committees, standing or special, appoint Directors to serve on such
     committees and confer such powers upon such committees and revoke such
     powers and terminate the existence of such committees, as the Board at its
     pleasure may determine, subject to the limitations set forth in Section
     8.40(c) of the Illinois Business Corporation Act of 1983, as amended from
     time to time.

          SECTION 7. Meetings of any committee of the Board may be called at any
     time by the Chairman, by any two Directors or by the chairman of the
     committee the meeting of which is being called and shall be held at such
     place as shall be designated in the notice of such meeting. Notice of each
     committee meeting stating the time and place at which such meeting will be
     held shall be given to each member of the committee personally, or by
     telegraph, or by depositing the same in the mails properly addressed, at
     least one day before the day of such meeting. A majority of the members of
     a committee shall constitute a quorum thereof but a lesser number may
     adjourn the meeting from time to time until a quorum is obtained, or may
     adjourn sine die. A majority vote of the members of a committee present at
     a meeting at which a quorum is present shall be necessary for committee
     action.

          SECTION 8. The Board of Directors may from time to time designate from
     among the Directors alternates to serve on one or more committees as
     occasion may require. Whenever a quorum cannot be secured for any meeting
     of any committee from among the regular members thereof and designated
     alternates, the member or members of such committee present at such meeting
     and not disqualified from voting thereat, whether or not he or they
     constitute a quorum, may unanimously appoint another member of the Board of
     Directors to act at the meeting in place of such absent or disqualified
     member.

         SECTION 9. Every Director of the Company, or member of any committee
     designated by the Board of Directors pursuant to authority conferred by
     these By-Laws, shall, in the performance of his or her duties, be fully
     protected in relying in good faith

                                     -11-
<PAGE>
 
     upon the records of the Company and upon such information, opinions,
     reports or statements presented to the Company by any of the Company's
     officers or employees, or committees of the Board of Directors, or by any
     other person as to matters the Director or member reasonably believes are
     within such other person's professional or expert competence and who has
     been selected with reasonable care by or on behalf of the Company.

            SECTION 10. Unless otherwise limited by the Board of Directors and
     subject to the limitations set forth in the next sentence, each committee
     of the Board of Directors consisting of two or more Directors may exercise
     the authority of the Board. Notwithstanding any other provision of the By-
     Laws, no committee of the Board of Directors shall: (1) authorize
     distributions; (2) approve or recommend to shareholders any act required by
     law to be approved by shareholders; (3) fill vacancies on the Board of
     Directors or on any of its committees; (4) elect or remove officers or fix
     the compensation of any member of the committee; (5) adopt, amend or repeal
     the By-Laws; (6) approve a plan of merger not requiring shareholder
     approval; (7) authorize or approve reacquisition of stock, except according
     to a general formula or method prescribed by the Board of Directors; (8)
     authorize or approve the issuance or sale, or contract for sale, of stock
     or determine the designation and relative rights, preferences, and
     limitations of a series of stock, except that a committee may fix the
     specific terms of the issuance or sale or contract for sale or the number
     of shares of stock to be allocated to particular employes under an employe
     benefit plan; or (9) amend, alter, repeal, or take action inconsistent with
     any resolution or action of the Board of Directors when the resolution or
     action of the Board of Directors provides by its terms that it shall not be
     amended, altered or repealed by action of a committee.

                                 ARTICLE V.

                                 OFFICERS.

            SECTION 1. There shall be elected by the Board of Directors, at its
     first meeting after the annual election of Directors in each year if
     practicable, the following principal officers of

                                      -12-
<PAGE>
 
     the Company, namely: a Chairman, a President, such number of Executive Vice
     Presidents, Senior Vice Presidents and Vice Presidents as the Board at the
     time may decide upon, a Secretary, a Treasurer and a Comptroller; and the
     Board may also provide for a Vice Chairman and such other officers, and
     prescribe for each of them such duties, as in its judgment may from time to
     time be desirable to conduct the affairs of the Company. No officer shall
     be elected for a term extending beyond the first day of the month following
     the month in which such officer attains the age of 65 years, on which date
     such officer shall be retired. The Chairman shall be a Director of the
     Company; any other officer above named may, but need not, be a Director of
     the Company. Any two or more offices may be held by the same person. All
     officers shall hold their respective offices until the first meeting of the
     Board of Directors after the next succeeding annual election of Directors
     and until their successors, willing to serve, shall have been elected, but
     any officer may be removed from office by the Board of Directors whenever
     in its judgment the best interests of the Company will be served thereby.
     Such removal, however, shall be without prejudice to the contract rights,
     if any, of the person so removed. Election of an officer shall not of
     itself create contract rights.

          SECTION 2. The Chairman shall be the chief executive officer of the
     Company and shall have general authority over all the affairs of the
     Company, including the power to appoint and discharge any and all officers,
     agents and employes of the Company not elected or appointed directly by the
     Board of Directors. The Chairman shall, when present, preside at all
     meetings of the shareholders and of the Board of Directors. The Chairman
     shall have authority to call special meetings of the shareholders and
     meetings of the Board of Directors, and of any committee of the Board of
     Directors and, when neither the Board of Directors nor the Executive
     Committee is in session, to suspend the authority of any other officer or
     officers of the Company, subject, however, to the pleasure of the Board of
     Directors or of the Executive Committee at its next meeting. The Chairman,
     or such other officer as the Chairman may direct, shall be responsible for
     all internal audit functions, and the internal audit personnel shall report
     directly to the Chairman or to such other officer.

                                      -13-
<PAGE>
          SECTION 3. If, at any time, it is brought to the attention of any
     Director that the Chairman has or may become absent or disabled and may
     thereby be unable to perform the duties of Chairman for some period of
     time, the Lead Director shall, as promptly as practicable upon his own
     initiative, or after notice from another Director, convene a meeting (in
     person or by telephone conference call) of the Outside Directors (who for
     purposes hereof shall consist of all Directors who are not and have never
     been employees of the Company or any of its direct or indirect
     subsidiaries) who shall decide whether the Chairman has become absent or
     disabled. Upon such determination, the Outside Directors shall designate an
     Acting Chairman, who may be the Lead Director or any other Director of the
     Company, and who shall exercise the power and duties of the Chairman until
     the Outside Directors shall have determined that the Chairman can resume
     his duties as Chairman or until a new Chairman has been elected by the
     Board of Directors. The Acting Chairman, however, shall have no authority
     to make changes in the persons holding any office at the executive payroll
     level of the Company or to make changes in any such person's duties or
     responsibilities, or compensation or benefits, without prior approval of
     the Board of Directors. For purposes of this Section, any action of the
     Outside Directors shall be by majority vote of those present at a meeting
     of such Directors, provided that a majority of such Directors shall
     constitute a quorum for such a meeting.

          SECTION 4. Except insofar as the Board of Directors, the Executive
     Committee or the Chairman shall have devolved responsibilities on the other
     principal officers, the President shall be responsible for the general
     management and direction of the affairs of the Company, subject to the
     control of the Board of Directors, the Executive Committee and the
     Chairman. The President shall have such other powers and duties as usually
     devolve upon the President of a corporation and such further powers and
     duties as may be prescribed by the Board of Directors, the Executive
     Committee or the chairman. The President shall report to the Chairman.

          SECTION 5. The Executive Vice Presidents, the Senior Vice Presidents
     and the Vice Presidents shall have such powers and duties as may be
     prescribed for them, respectively, by the Board of Directors, the Executive
     committee or the Chairman. Each of

                                      -14-
<PAGE>
 
     such officers shall report to the Chairman or such other officer as the
     Chairman shall direct.

          SECTION 6. The Secretary shall attend all meetings of the
     shareholders, of the Board of Directors and of each committee of the Board
     of Directors, shall keep a true and faithful record thereof in proper books
     and shall have the custody and care of the corporate seal, records, minute
     books and stock books of the Company and of such other books and papers as
     in the practical business operations of the Company shall naturally belong
     in the office or custody of the Secretary or as shall be placed in the
     Secretary's custody by order of the Board of Directors or the Executive
     Committee. The Secretary shall keep or cause to be kept a suitable record
     of the addresses of shareholders and shall, except as may be otherwise
     required by statute or the by-laws, sign and issue all notices required for
     meetings of shareholders, of the Board of Directors and of the committees
     of the Board of Directors. Whenever requested by the requisite number of
     shareholders or Directors, the Secretary shall give notice, in the name of
     the shareholder or shareholders or Director or Directors making the
     request, of a meeting of the shareholders or of the Board of Directors or
     of a committee of the Board of Directors, as the case may be. The Secretary
     shall sign all papers to which the Secretary's signature may be necessary
     or appropriate, shall affix and attest the seal of the Company to all
     instruments requiring the seal, shall have the authority to certify the by-
     laws, resolutions of the shareholders and Board of Directors and committees
     of the Board of Directors and other documents of the Company as true and
     correct copies thereof and shall have such other powers and duties as are
     commonly incidental to the office of Secretary and as may be prescribed by
     the Board of Directors, the Executive Committee or the Chairman. The
     Secretary shall report to the Chairman or such other officer as the
     Chairman shall direct.

          SECTION 7. The Treasurer shall have charge of and be responsible for
     the collection, receipt, custody and disbursement of the funds of the
     Company. The Treasurer shall deposit the Company's funds in its name in
     such banks, trust companies or safe deposit vaults as the Board of
     Directors may direct. Such funds shall be subject to withdrawal only upon
     checks or drafts signed or authenticated in such manner as may be
     designated from time to time by resolution of the Board of Directors or of
     the

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<PAGE>
 
     Executive Committee. The Treasurer shall have the custody of such books and
     papers as in the practical business operations of the Company shall
     naturally belong in the office or custody of the Treasurer or as shall be
     placed in the Treasurer's custody by order of the Board of Directors or the
     Executive Committee. The Treasurer shall have such other powers and duties
     as are commonly incidental to the office of Treasurer or as may be
     prescribed for the Treasurer by the Board of Directors, the Executive
     Committee or the Chairman. Securities owned by the Company shall be in the
     custody of the Treasurer or of such other officers, agents or depositaries
     as may be designated by the Board of Directors or the Executive Committee.
     The Treasurer may be required to give bond to the Company for the faithful
     discharge of the duties of the Treasurer in such form and in such amount
     and with such surety as shall be determined by the Board of Directors. The
     Treasurer shall report to the Chairman or such other officer as the
     Chairman shall direct.

          SECTION 8. The Comptroller shall be responsible for the executive
     direction of the accounting organization and shall have functional
     supervision over the records of all other departments pertaining to
     revenues, expenses, money, securities, properties, materials and supplies.
     The Comptroller shall prescribe the form of all vouchers, accounts and
     accounting procedures, and reports required by the various departments. The
     Comptroller shall be responsible for the preparation and interpretation of
     all accounting reports and financial statements as required and for the
     proper review and approval of all bills received for payment. No bill or
     voucher shall be so approved unless the charges covered by the bill or
     voucher shall have been previously approved through job order, requisition
     or otherwise by the head of the department in which it originated, or
     unless the Comptroller shall otherwise be satisfied of its propriety and
     correctness. The Comptroller shall have such other powers and duties as are
     commonly incidental to the office of Comptroller or as may be prescribed
     for the Comptroller by the Board of Directors, the Executive Committee or
     the Chairman. The Comptroller may be required to give bond to the Company
     for the faithful discharge of the duties of the Comptroller in such form
     and in such amount and with such surety as shall be determined by the Board
     of Directors. The Comptroller shall report to the Chairman or such other
     officer as the Chairman shall direct.

                                     -16-
<PAGE>
 
          SECTION 9. Assistant Secretaries, Assistant Treasurers and Assistant
     Comptrollers, when elected or appointed, shall respectively assist the
     Secretary, the Treasurer and the Comptroller in the performance of the
     respective duties assigned to such principal officers, and in assisting
     such principal officer, each of such assistant officers shall for such
     purpose have the powers of such principal officer. In case of the absence,
     disability, death, resignation or removal from office of any principal
     officer, such principal officer's duties shall, except as otherwise ordered
     by the Board of Directors or the Executive Committee, temporarily devolve
     upon such assistant officer as shall be designated by the Chairman.

          SECTION 10. At least once each year, the Chairman shall report (which
     may be oral) to the Outside Directors (who for purposes hereof shall
     consist of all Directors who are not and never have been employees of the
     Company or any of its direct or indirect subsidiaries) on the status of a
     plan for succession to the office of Chairman.

                                 ARTICLE VI.

                                 INDEMNIFICATION.

          SECTION 1. (a) A Director of the Company shall not be personally
     liable to the Company or its shareholders for monetary damages for breach
     of fiduciary duty as a Director, except for liability (i) for any breach of
     the Director's duty of loyalty to the Company or its shareholders, (ii) for
     acts or omissions not in good faith or that involve intentional misconduct
     or a knowing violation of law, (iii) under Section 8.65 of the Illinois
     Business Corporation Act of 1983, as amended, or (iv) for any transaction
     from which the Director derived an improper personal benefit. If the
     Illinois Business Corporation Act of 1983 is amended to authorize corporate
     action further eliminating or limiting the personal liability of Directors,
     then the liability of a Director of the Company shall be eliminated or
     limited to the full extent permitted by the Illinois Business Corporation
     Act of 1983, as so amended. Any repeal or modification of this Section 1(a)
     by the shareholders of the Company shall not adversely affect any right or
     protection of a Director of the Company existing at the time of such repeal
     or modification.

                                     -17-
<PAGE>
 
          (b) Each person who is or was or had agreed to become a Director or
     officer of the Company, and each person who is or was serving or who had
     agreed to serve at the request of the Board of Directors or an officer of
     the Company as an employe or agent of the Company or as a director,
     officer, employe, or agent, trustee or fiduciary of another corporation,
     partnership, joint venture, trust or other enterprise (including the heirs,
     executors, administrators or estate of such person), shall be indemnified
     by the Company to the full extent permitted by the Illinois Business
     Corporation Act of 1983 or any other applicable laws as presently or
     hereafter in effect. Without limiting the generality of the foregoing, the
     Company may enter into one or more agreements with any person which provide
     for indemnification greater or different than that provided in this Section
     1(b). Any repeal or modification of this Section 1(b) shall not adversely
     affect any right or protection existing hereunder immediately prior to such
     repeal or modification.

          SECTION 2. The provisions of this Article shall be deemed to be a
     contract between the Company and each Director or officer who serves in any
     such capacity at any time while this Article is in effect, and any repeal
     or modification of this Article shall not affect any rights or obligations
     hereunder with respect to any state of facts then or theretofore existing
     or any action, suit or proceeding theretofore or thereafter brought or
     threatened based in whole or in part upon any such state of facts.

          SECTION 3. The indemnification provided or permitted by this Article
     shall not be deemed exclusive of any other rights to which those
     indemnified may be entitled by law or otherwise, and shall continue as to a
     person who has ceased to be a Director, officer, employee or agent and
     shall inure to the benefit of the heirs, executors and administrators of
     such person.

          SECTION 4. The Company may purchase and maintain insurance on behalf
     of any person who is or was a Director, officer, employee or agent of the
     Company, or who is or was serving at the request of the Company as a
     director, officer, employee or agent of another corporation or of a
     partnership, joint venture, trust or other enterprise, against any
     liability asserted against such person and incurred by such person in any
     such capacity, or arising out of his or her status as such, whether or not
     the
 
                                     -18-
<PAGE>
 
     Company would have the power to indemnify such person against such
     liability under the laws of the State of Illinois.

                                 ARTICLE VII.

                                 MISCELLANEOUS.

          SECTION 1. No bills shall be paid by the Treasurer unless reviewed and
     approved by the Comptroller or by some other person or committee expressly
     authorized by the Board of Directors, the Executive Committee, the Chairman
     or the Comptroller to review and approve bills for payment.

          SECTION 2. All checks, drafts or other orders for payment of money
     issued in the name of the Company shall be signed by such officers,
     employees or agents of the Company as shall from time to time be designated
     by the Board of Directors, the Chairman, the chief financial officer of the
     Company or the Treasurer.

          SECTION 3. Any and all shares of stock of any corporation owned by the
     Company and any and all voting trust certificates owned by the Company
     calling for or representing shares of stock of any corporation may be voted
     at any meeting of the shareholders of such corporation or at any meeting of
     the holders of such certificates, as the case may be, by any one of the
     principal officers of the Company upon any question which may be presented
     at such meeting, and any such officer may, on behalf of the Company, waive
     any notice required to be given of the calling of such meeting and consent
     to the holding of any such meeting without notice. Any such principal
     officer other than the Secretary, acting together with the Secretary or an
     Assistant Secretary, shall have authority to give to any person a written
     proxy, in the name of the Company and under its corporate seal, to vote any
     or all shares of stock or any or all voting trust certificates owned by the
     Company upon any question that may be presented at any such meeting of
     shareholders or certificate holders, with full power to waive any notice of
     the calling of such meeting and consent to the holding of such meeting
     without notice.

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<PAGE>
 
          SECTION 4. The fiscal year of the Company shall begin on the first day
     of January and end on the last day of December in each year.

                                 ARTICLE VIII.

                  ALTERATION, AMENDMENT OF REPEAL OF BY-LAWS.

          These by-laws may be altered, amended or repealed by the shareholders
     or the Board of Directors.

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